Purpose: To characterize the environment in both ground and aerial ambulances in an effort to identify and quantify the risk factors associated with intraventricular hemorrhage (IVH) in preterm infants, with the goal of developing a device to mitigate this problem.

Methods: A small, stand-alone battery operated device was developed to characterize the environment inside neonatal transports. This device included an array of sensors to measure acceleration forces, sound levels, temperature, pressure, and light intensities. Two of the data acquisition devices were used to collect data inside and outside the transport incubator simultaneously for a period of thirty minutes during a test flight in a transport helicopter. Real-time digital signal processing was performed for the sound signals to reduce data. Furthermore batch digital signal processing was performed on an external computer to calculate the vibration spectrograms, occurrence of impulsive forces, and variations in ambient temperature, pressure and luminance. The results were compared between the two devices to determine whether the current transport incubator design is reducing or increasing the suspected risk factors.

Results: The vibration levels registered in the transport incubator during flight were five times greater than in the crew cabin in the vertical direction. High vibration levels were registered in the horizontal direction in the transport incubator, which were not registered in the crew cabin. In contrast, vibration in lateral direction was nearly half of that registered in the crew cabin. Sound levels were on average 70 dBA in the transport incubator. Luminance levels reached values up to 6920 Lux. No major changes in temperature and pressure were registered.

Conclusions: IVH is a serious consequence of transporting preterm infants from one health care facility to another and occurs in roughly one out of three infants. To address this problem, a transport monitoring device can help characterize the environment in these transports in an effort to design a new state of the art transport incubator to mitigate this problem.